Interaction of NS2 with AIMP2 Facilitates the Switch from Ubiquitination to SUMOylation of M1 in Influenza A Virus-Infected Cells
Interaction of NS2 with AIMP2 Facilitates the Switch from Ubiquitination to SUMOylation of M1 in Influenza A Virus-Infected Cells
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DOI：
10.1128/jvi.02170-14
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发表时间：
2015-01-01
影响因子：
5.4
通讯作者：
Huang, Wenlin
中科院分区：
文献类型：
--
作者：
Gao, Shijuan;Wu, Jiaoxiang;Huang, Wenlin
甲型流感病毒（IAV）依赖于宿主因子来支持其生命周期，因为病毒蛋白质劫持或与细胞蛋白质相互作用以执行其功能。这些因素的识别和理解将增加我们对病毒操纵的分子机制的了解。在这项研究中，我们寻找新的结合伙伴的流感病毒NS 2蛋白，核输出蛋白负责克服宿主范围的限制，通过酵母双杂交筛选试验和谷胱甘肽S-转移酶下拉和免疫共沉淀试验，并确定AIMP 2，一种有效的肿瘤抑制因子，通常功能调节蛋白质的稳定性，作为一个主要的NS 2结合候选人。我们发现，NS 2的存在下，保护AIMP 2从泛素介导的降解在NS 2转染细胞和AIMP 2作为一个积极的调节IAV复制。有趣的是，AIMP 2对NS 2没有显著影响，但增强了基质蛋白M1的稳定性。此外，我们提供的证据表明，AIMP 2招聘开关的修饰M1的泛素化SUMO化，这发生在相同的附着位点（K242）上的M1，从而促进M1介导的病毒核糖核蛋白复合物核输出，以增加病毒复制。总的来说，我们的研究结果揭示了一个新的机制AIMP 2调解流感病毒replication.IMPORTANCE虽然在IAV感染的M1的泛素化已被观察到，精确的修改网站和这种修改的分子后果仍然模糊。在这里，我们第一次证明，泛素和SUMO竞争相同的赖氨酸（K242）的M1和NS 2与AIMP 2的相互作用，促进开关的M1修饰泛素化SUMO化，从而增加病毒复制。
Influenza A viruses (IAVs) rely on host factors to support their life cycle, as viral proteins hijack or interact with cellular proteins to execute their functions. Identification and understanding of these factors would increase our knowledge of the molecular mechanisms manipulated by the viruses. In this study, we searched for novel binding partners of the influenza A virus NS2 protein, the nuclear export protein responsible for overcoming host range restriction, by a yeast two-hybrid screening assay and glutathione S-transferase-pulldown and coimmunoprecipitation assays and identified AIMP2, a potent tumor suppressor that usually functions to regulate protein stability, as one of the major NS2-binding candidates. We found that the presence of NS2 protected AIMP2 from ubiquitin-mediated degradation in NS2-transfected cells and AIMP2 functioned as a positive regulator of IAV replication. Interestingly, AIMP2 had no significant effect on NS2 but enhanced the stability of the matrix protein M1. Further, we provide evidence that AIMP2 recruitment switches the modification of M1 from ubiquitination to SUMOylation, which occurs on the same attachment site (K242) on M1 and thereby promotes M1-mediated viral ribonucleoprotein complex nuclear export to increase viral replication. Collectively, our results reveal a new mechanism of AIMP2 mediation of influenza virus replication.IMPORTANCE Although the ubiquitination of M1 during IAV infection has been observed, the precise modification site and the molecular consequences of this modification remain obscure. Here, we demonstrate for the first time that ubiquitin and SUMO compete for the same lysine (K242) on M1 and the interaction of NS2 with AIMP2 facilitates the switch of the M1 modification from ubiquitination to SUMOylation, thus increasing viral replication.